Traveling is notoriously harsh on immune system health. Whether you're in a plane, train or automobile, being in an enclosed space for a few (or several!) hours with others can allow the spread of germs from one person to the next quite easily.

But the stress of travel can also contribute to poor immune health. Maybe flying makes you nervous, there's a screaming baby on your plane, you just don't sleep well sitting up or you go stir-crazy if you can't get any exercise. You can boost your immune system with antibiotics and other supplements, but how can you take care of those pesky elevated stress levels and the desire to just move? Here are some exercises to stay mentally and physically healthy during your business or leisure travel:

Hotel room bodyweight workouts
If your hotel doesn't have a weight room or even a lone treadmill, never fear! You can get a great cardio workout while working your entire body – legs, chest, shoulders, triceps, biceps, back and abs – with just your body weight, 20 minutes and standard hotel room implements like a bed, desk and chair. Here are several easy exercises to do in your hotel room:

Do bodyweight squats with arms outstretched, making sure your knees are in proper position.

Use the edge of the bed or, if you're tall, the ubiquitous hotel room desk to do inclined pushups, keeping your feet on the floor.

Do the plank, which can be done anywhere.

Do some jumping squats – they aren't pretty, but they sure do work. Only do them in your hotel room if you have tall ceilings so as not to injure your fingers on the upswing.

Tricep​s dips can be done off the edge of a bed or chair.

In lieu of weights, do one-armed luggage rows – provided you have a small suitcase. The nice thing about suitcases is that you can pack or unpack as much as you need to get the proper weight.

Lunges are easy to do anywhere as well.

If you don't mind touching the hotel room floor (some people are picky) you can add in crunches, reverse crunches and pushups.

Pick and choose from the activities above and do several continuous reps for the best cardio workout, but go at your own pace.

Other workout options

Yoga is a great way to reduce stress. If you get particularly stressed while flying, check out this article about the many different yoga positions that you can do on an airplane. There are great options for both seat and aisle positions, provided you don't mind a few confused looks from other passengers.

Check out local jogging trails or parks ahead of time for the places you're visiting. There are likely some runners forums online that mention good running paths no matter what city you're in.

Check ahead of time to see if your hotel has a gym or pool, and don't forget your sneakers, workout clothes or swimsuit.

Bring easy-to-pack workout items like jump ropes, ankle swim weights, dumbbells you can fill with water or resistance bands.